Higashimatsuyama, Saitama, Japan (March
31, 2014): HREM Research Inc. introduced Jitterbug for DigitalMicrograph at the
end of March 2014. The Jitterbug corrects instability of probe scanning system
(scan noise), and restores resolution before degradation, and improves image
quality. Furthermore, the Jitterbug corrects drift of scan image of crystalline
materials using periodicity of the sample.

Procedures of Jitterbug have been
developed by Lewys Jones and Peter Nellist of University of Oxford [1], and may
be well applied for a scanning system, such as a scanning transmission electron
microscope (STEM). In STEM, instabilities at high frequencies will result in
so-called escan-noisef, and this is clearly seen in the jagged/torn columns of
the atomic resolution dark field image shown in the left half of the figure
below.

It is now possible to observe these
characteristic distortions and to mitigate their effects using the Jitterbug.
The magnitude of the scan-distortion at each point is determined by comparing
the region about each pixel with neighbouring scan lines above and below. With
all the distortions diagnosed, it is possible to restore an image with
significantly reduced scan-noise as shown in the right half of the figure. In
this example, image resolution was improved from 88.7pm to 75.1 pm (15.3%
better) and SNR was improved from 2.04 to 3.76 (84.3%) [1].

Founded in 2001, HREM Research Inc.
specializes in developing products and services that enhance High-Resolution
Electron Microscopy (HREM). Dr. Kazuo Ishizuka, the founder of a company has
established the whole technique for HREM image simulation. Thus, a company's
flagship product, Mac/WinHREM, is a world leading HREM image simulation
software. Currently, HREM Research Inc. is actively working on making useful
techniques to be available for the HREM community. For more information, visit
http://www.hremresearch.com or contact support@hremresearch.com.

Contact:

Kazuo Ishizuka

HREM Research Inc.

14-48
Matsukazedai, Higashimatsuyama

355-0055
JAPAN

Supplementary materials

Dark-field STEM image of [100] oriented SrTiO3, before scan-noise
and drift correction (left) and after (right). In the left half of the image,
the atomic columns appear jagged and torn and the square symmetry of the
crystal lattice is heavily sheared. (image width = 5nm)